Background render tutorial

Follow the next script to create one of the simplest animation using the data provided within BlenderNC. It can be run (on MacOS) with the line

/Applications/Blender.app/Contents/MacOS/Blender -b - P background.py

import bpy
file = "/path/2/file/" # Replace this line with the path to the datacube
var = "var_name" # Replace this line with the variable name (str)

node_groups = bpy.data.node_groups
node_groups_keys = node_groups.keys()

for node_groups_name in node_groups_keys:
    if "BlenderNC" in node_groups_name:
        node_groups.remove(node_groups[node_groups_name])

bpy.data.node_groups.new("BlenderNC", "BlenderNC")

node_tree = bpy.data.node_groups["BlenderNC"]
node_tree.use_fake_user = True

# Create nodes
path = node_tree.nodes.new("datacubePath")
path.location = (-350, 0)
inp = node_tree.nodes.new("datacubeNode")
inp.location = (-125, 0)
res = node_tree.nodes.new("datacubeResolution")
res.location = (125, 0)
out = node_tree.nodes.new("datacubeOutput")
out.location = (350, 0)

# Select variable
path.blendernc_file = file
# Connect path node to datacube node
node_tree.links.new(inp.inputs[0], path.outputs[0])
# Select variable
inp.blendernc_datacube_vars = var
# Change resolution
res.blendernc_resolution = 100

# Connect links
node_tree.links.new(res.inputs[0], inp.outputs[0])
node_tree.links.new(out.inputs[0], res.outputs[0])

# Create new image
bpy.ops.image.new(
    name="BlenderNC_default",
    width=1024,
    height=1024,
    color=(0.0, 0.0, 0.0, 1.0),
    alpha=True,
    generated_type="BLANK",
    float=True,
)

# Assign new image to node
out.image = bpy.data.images.get("BlenderNC_default")

# Delete cube
object_keys = bpy.data.objects.keys()

if "Cube" in object_keys:
    bpy.data.objects["Cube"].select_set(True)  # Blender 2.8x
    bpy.ops.object.delete()

if "Plane" not in object_keys:
    bpy.ops.mesh.primitive_plane_add()

plane = bpy.data.objects["Plane"]
plane.select_set(True)

image_size_x = out.image.pixels.data.size[0]
image_size_y = out.image.pixels.data.size[1]

if image_size_x < image_size_x:
    ratio = image_size_y / image_size_x
else:
    ratio = image_size_x / image_size_y

plane.scale[0] = ratio

bpy.ops.blendernc.apply_material()

scene = bpy.context.scene
render = scene.render
directory = bpy.path.abspath("//")

format = file.split(".")[-1]
render.filepath = f"{directory}" + "{0}_image_{1}.png".format(var, format)
bpy.ops.render.render(write_still=True)

render.filepath = directory